A fuel cell system is an electro-chemical device that includes an anode and a cathode with an electrolyte therebetween. The anode receives a fuel such as hydrogen and the cathode receives an oxidant such as oxygen or air. When the fuel is supplied to a reaction plane of the anode via an anode loop, the fuel is ionized and the fuel ions are transferred to the cathode via a solid polymer electrolyte membrane. During this process, electrons are generated and flow to an external circuit, providing direct current electric energy. As the oxidant is supplied to the cathode via a cathode loop, the fuel ions, electrons, and the oxidant react at the cathode and produce water. The water is exhausted from the fuel cell system by means of a cathode exhaust passage. Typically, not all of the water is exhausted from the fuel cell system. An exemplary fuel cell system is shown and described in Assignee's co-pending U.S. Pat. Appl. Pub. No. 2009/0208795 to Skala et al., the entire disclosure of which is hereby incorporated herein by reference.
Valves are typically disposed in the anode loop to control various flows and parameters of the fuel such as a pressure and a temperature of the fuel within the fuel cell system, for example. One such anode valve controls a flow of the fuel to the cathode for warm-up of the fuel cell system in a low-temperature environment. If water remains in the anode loop after fuel cell system shutoff, and the fuel cell system is maintained in the low-temperature environment, the water remaining in the anode valve may freeze and form ice. The ice may form a blockage in the anode valve and prevent normal operation of the anode valve. When the anode valve is not operating normally, it may be difficult to restart the fuel cell system, which is undesirable.
There is a continuing need for an anode valve for a fuel cell system that militates against ice formation and blockage. Desirably, the anode valve is sealed to militate against ice buildup during fuel cell system shutoff.